Bit



Patented Aug. 27, 1929. l

UNITED STATES PATENT OFFICE.

JAMES H. SWIFT, F HUNTINGTON PARK, AND LLOYD DALLDORF, 0F SOUTHGATE CALU'OBNIA.

BIT.

Application led 'Iay 3, 192. Serial No. 106,541.

This invention has to do with a bit, and

it is an object of the invention to provide a bit which is effective and practical for the drilling of wells, or the like. It is an object of the present invention to provide a bit suitable for well drilling which comprises movable cutters which cooperate to keep each other clean and in proper operating condition.

It is another object of the invention to provide a bit of the character specified c0m prising movable cutting parts wlnch operate in synchronism.

A further object of the present invention is to provide a bit of the character described with cutters presenting a plurality of durf able and effective cutting edges.

The various objects and features of our invention wi-ll be best and more fully understood from the following detailed descri tion of a typical preferred form and app icationof the invention, throughout which description we refer to the accompanying drawings, in which:

Fig. 1 isa side elevation of, a welldrilling bit embodying the invention;

Fig. 2 -is an enlarged side elevation of a portion of the bit showing 'certainparts vin section;

Fig. 3 is a detailed sectional view` taken substantially as indicated by `line 3-3 on- Fig. 2; and

Fig. 4 is an enlarged detailed section taken substantially. as indicated by line 4--4 on Fig. 2

generally, a body 10, side cutters 11,'and a central -connecting cutter 12.

The body may, in accordance with the broader principles fof our invention, be shaped and proportioned to pro rly carry the cutters and may be adapte to be attached to any' suitable operating member. In the case of a well bit, such as we have chosen to set forth in this disclosure of our invention, the body 10 may bein the form of a forging, thelower portion of which is shaped and proportioned'to properly carry the cutters. The upper end portion of the body is provided with a ta ered screw threaded pin 15 whereby the ody can. be attached to a string of drill pipe, or the like. In accordance with our invention the bit is provided with two or more side cutters 11 The .bit which we have provided includes,

which are vertically disposed or mounted so that their axes are parallel with the vertical or longitudinal axis of the body. In the form of the invention shown in the drawings there are two side cutters 11 mounted in spaced relation and for operation about axes located at diametrically op osite sides of the central vertical axis of t e body 10. In accordance with our invention each side cutter 11 is provided with one or more cuttin ed es adapted to project beyond the utters are mounted on or at the lower end of the body 10 so that their cutting parts are below the bod and project laterally beyond the line of t e side of the body. In tie preferred form of our invention each side cutter 11 includes a plurality of helical blades 18 formed symmetrically around or projecting from a central hub 19. In (practice the hub 19 is comparatively long an the blades extend longitudinally of the hub and spirally around it, as clearly shown throughout the drawings. The lower ends of the blades may project below the lower end of the hub and may be finished with suitable end cutting edges 20. The side or outer edges of the blades are finished to present cutting edges 21.- In the particular case shown in the drawings, each cutter is provided with five blades spaced 72 apartl around the axis of the hub. The cutters 11 ma be mounted on or connected tothe lower en portion of the body in any suitable manner. For instance, each cutter may be provided with a projection or stem 22 to be rotatably carried in a socket or opening 23 formed in the lower end of the body. The

stem may be in the form of an extension or continuation of the hub of the cutter and may be turned or otherwise finished so that it is round in cross sectional configuration. In practice the stem of the cutter may be retained in proper position in the. opening 23 by any suitable means. construction shown in the drawings a bushing or liner 26 is provided in the o ening 23 to form a bearing for the stem. n this case a head 27 is provided on the upper endl of the stem above the upper end of the bushing and the bushing is split longitudinally or 4ttorrned in two sections whereby it can be assembled around the stem below the head to allow the partsto be assembled tothe position shown in Fig. 2 of the drawings.

In the particular -ly of a central hub 19.

One or more retaining pins may be provided in the body to engage the sections of the bushin to retain them in the opening'23 of the bo Further, if desired, the retaining pins, w ich may be in the form of screws, may be carried by or in the body 10 to extend intoa recess or groove 28 formed in the stem. In the construction which we have ust described and which is clearly shown 1n -the drawings, the retaining pins hold the bushing sections in place and the bushing sections operate to revent displacement of the stem because o the head on the upper end of the stem. Further, if the retaining pins extend into a groove inthe stem they will directly operate to retain the stem in place. #It is desirable to provide means for taking the u y thrust which comes upon the cutters, and or this purpose thrust bearings of suitable design may be provided be-Y tween the upper ends of the cutter stems and the endsvof the openings in the body. In the' drawings we have shown thrust bearing plates 30 inserted between the heads on the stems and the ends 31 of the openings in the body. This is a form of t rust bearing which is simple and reliable and which is particularly effective in tools of this character.

The center or connecting cutter 12 is, in accordance with the broader. featurescf our invention, vprovided as` an interconnection between the' side cutters whereby they are connected to operate in synchronlsm, and it is also provided with cutting parts whereby it may act as a cutter to aid the side cutters. YThe cutter 12 is located between the side cutters, and in the particular bit-shown in the drawings, is located centrally between the side cutters and concentric with thel longitudinal axis of the bod 10. The cutter 12 may be formed or shaped in much the same manner as the side cutters, that is it ma be provided with a pluralit of helical b ades 18 which extend longitudinal- The cutter 12 may be mounted for rotation through a stem '22 in the same manner as the side cutters. In accordance with our invention the blades of the cutters 11 and 12 are related and proportioned to mesh together inthe manner most clearly1 shown in ig. 3 of the drawings so that t e central cutter gears together orinterconnects' the two side cutters so that rotary movement is communicated between the cutters. If the central cutter 12 is to be an active cutting element, it may be extended to be substantially the same length as the slide cutters 4and the lower ends o? its blades may be provided with cutting edges 38 to Y operate on the bottom of the hole formed by the bit, and its side ed s may be finished to form cutting ed ii this connection it may, in practice, e desirable to form the which is'clearly illustrated in end cutting edges 20 of the cutters 11 at an angle as shown in the drawings.

With the construction Athat we have set forth the center cutter 12 interconnects the side cutters 11 so that they rotate in the same direction as the body of the bit is rotated inthe hole. During operation the body 10 'l is rotated in the direction indicated by the arrow A in Fig. 3 causing the cutting edges of the side cutters to engage the' side and bottom of the hole with the result that the side cutters are caused to rotate in the direction indicated by the arrow B in Fig. 3.' The side cutters 11 are made to rotate in synchronism or at substantially the same rate by the interconnection formed by the center cutter 12. For instance if there is a tendency for one of the side cutters to operate at a rate different from the other the center cutter 'forms a connection between the two side cutters which equalizes the operation of the same manner. By making the side cutters comparatively long, as shown in the drawings, the side cutting edges 21 are comparatively long and thus present long cutting parts whichlwill effectively act on the material at the sides of the hole and cause positive turning of the cutters. Further,

the blades of the several cutters in intermeshf that the side cutters can not -be driven by the center cutter', in which case shoulders 50 may beprovided at the trailing sides 62 of the blades of the'side cutters to be engaged by the blades of the center cutter in the event that the blades of the'center cutter operate on 'the side cutters tending -to drive them. Withl this shoulder Fig. 3 one ofy construction, i

the side cutters cannot operate to rive or act as the sole means of propulsion of the other side cutter, but, in the' case of one sidek cutter tending to drive the other the construction just described o crates to lock all of the cutters against re ative rotation so that the cutters operate as a unit with the bod until the tendency for one side cutter to rive the other is passed. Further, in operation the blades of the helical or spirall formed as above described and as clearly s own throughout the drawings and in meshing as we have described,

cutters being 85 v side cutters causing them to operate in the tend to lfeed the cuttings upwardly so that they will readily pass out of the hole. ,For the purpose of circulation suitable circulation openings 65 may be provided in the body to discharge downwardly from the v -lower end of the body at a point or in a Ameshing blades.

Aab y carried manner4 to wash the blades of the' cuters and thereby further keep the parts in proper operating condition.

Having described only a typical preferred form of my invention I do not wis to limit myself to the specific details set forth, but wish 4to reserve to myself any changes or variations that may appear to those skilled in the art or fall within the scope of the' following claims.

Havin described our invention we claim:

1. A bit of the character described including a body, and la plurality of cutters rotatably carried by the body,

2, A bit' ofthe character 'describedim cluding a body rotatably carried by the body, the cutters havin meshin helical blades.

3. i bit of t e character described includ? a body, and a plurality of cutters rotatby the body, 'the cutters having meshing blades with cutting edges and' havarallel axes of rotation.l

4. A bit of the character described includi l ing a body, and a plurality of cutters rotatab y carried by the body the cutters having meshing blades with Aside and end cutting edgesand having arallel axes of rotation. 5. A bit of the Ac aracter described includ- Y ing a body, two .cutters carried by the body and having spaced axes of rotation, and cutting parts on the cutters directly operatively connecting the cutters.

6. A bit of the character described including a body, two-spaced rotatable cutters carthe cutters having' and a plurality of cutters,

ried by the body and having helical blades, and a connectin cutter between said cutters with bladesmes 'ng with the blades of said cutters.

7. A bit of the ing a body, two spaced rotatable cutters carried by the body and havin` helical blades, with end and side cutting e es, and a connecting cutter between sai blades meshing with the blades of said cut-l ters.

8. A bit of the character described including a body, a plurality of interconnectedrotatable cutters carried by the body, and means whereby the cutters are operable in one'direction only.

9. A bit of the character described 'includv ing a body having openin s in its lower end, a plurality of cutters, an stems on the cutters rotatably carried in the openings,.the cuttersv having blades which intermesh and having parallel axes of rotation.

10. A bit of the character described including a body having openings in its lower `end, a plurality of cutters, stems on the cutters rotatably carried in the openings, the cutters having blades which intermesh and having parallel axes of rotation, and means for retaining the stems in the openings.

`11. A bit of the character described including a body having openings in its lower end,a plurality of cutters, stems 'on the cutters rotatably carried'in the openings, the cutters having blades which intermesh and having parallel axes of rotation, thrust bearings in nnection with the stems, and means for retaining the stems in the o nings.

' In witness that we claim t e foregoing character described includcutters with we have hereunto subscribed our name this 12th.day of March 1926.

LLOYD DALLDORF. JAMES H. SWIFT. 

